Field of the invention: This invention relates to apparatus and methods for sphere decoding of signals for MIMO detection, to receivers having such apparatus, and to corresponding computer programs for carrying out such methods.
Sphere decoding is a known algorithm and is regarded as providing the best BER vs. SNR (average bit error rate given a certain signal to noise ratio) for multi antenna communication systems using MIMO (Multiple input multiple output) based receivers (e.g. cellular (LTE), connectivity (WLAN IEEE 802.11n), etc.) and therefore can be a key part of a baseband processor for such systems. These methods involve determining the shortest Euclidean distance to ascertain the symbol vector which was transmitted with the greatest degree of probability. These approaches are thus used for sphere decoding for a hard decision receiver concept or producing log likelihood ratios for a soft decision output.